Sinornithosaurus

"Chinese bird-lizard"

Generic raptor body-plan outline
You 1.8 m (5.9 ft) tall
Sinornithosaurus 1.2 m (3.9 ft) long
as long as 2 people standing fingertip to fingertip
generic raptor body plan, scaled to length — not a silhouette of Sinornithosaurus
Length
1.2 m (3.9 ft)
Period
Early Cretaceous (125.46–124.12 Mya)
Place
Asia · China
Food
Carnivore
Clade
Dromaeosauridae Dinosauria Saurischia Theropoda Coelurosauria Sickle-clawed raptors: Velociraptor, Deinonychus, Utahraptor.

Sinornithosaurus (derived from a combination of Latin and Greek, meaning ‘Chinese bird-lizard’) is a genus of feathered dromaeosaurid dinosaur from the early Cretaceous Period (late Barremian) of the Yixian Formation in what is now China. It was the fifth non–avian feathered dinosaur genus discovered by 1999. The original specimen was collected from the Sihetun locality of western Liaoning. It was found in the Jianshangou beds of the Yixian Formation, dated to 124.5 million years ago. Additional specimens have been found in the younger Dawangzhangzi bed, dating to around 122 million years ago.

Xu Xing described Sinornithosaurus and performed a phylogenetic analysis which demonstrated that it is basal, or primitive, among the dromaeosaurs. He has also demonstrated that features of the skull and shoulder are very similar to Archaeopteryx and other avialans.

What we know

  • Named by Xu, Wang & Wu, 1999.
  • Body length estimated at about 1.2 m.
  • Fossils found in Asia and China.

What we guess

The reconstruction notes for Sinornithosaurus — soft tissue, color, behavior — haven't been written up yet. Only the recorded basics above are filled in so far.